Field of the Invention
The invention relates in general to a touch system, and more particularly, to a technology for correcting sensing results of a touch panel.
Description of the Related Art
Operating interfaces of recent electronic products have become more and more user-friendly and intuitive as technology advances. For example, via a touch screen, a user can directly operate programs as well as input messages/texts/patterns with fingers or a stylus; in this way, it is much easier to convey demands than operating via traditional input devices such as a keyboard or buttons. In practice, a touch screen usually includes a touch sensing panel and a display device disposed at the back of the touch sensing panel. According to a position of a touch on the touch sensing panel and a currently displayed image on the display device, an electronic device determines an intention of the touch to execute corresponding operations.
Current touch control techniques are in general categorized into resistive, capacitive, electromagnetic, ultrasonic and optic types. Regardless of the type of a touch panel, a certain error exists between an actual touch position and a touch position determined by an electronic device. Such detection error may lead the electronic device to misjudging a user intention to further result in an unintended operation. Therefore, a correction mechanism is necessary.
In a conventional correcting method, a look-up table storing various possible sensing results and corresponding correction results is usually required. Taking a sensing result represented in two-dimensional x-coordinate (X) and y-coordinate (Y) for example, the look-up table needs to store an N sets of original two dimensional x-coordinates (X) and y-coordinates (Y) and an N set of corresponding corrected two-dimensional x-coordinates (X″) and y-coordinates (Y″). Such method suffers from a drawback of requiring an enormous amount of memory space. As a touch control area provided by an electronic product expands, the memory space of the above conventional correcting method is also multiplied to cause to increased hardware costs.